/**
 * <h1>Expression</h1>
 * <pre>
 * 
 * </pre>
 * @author: chaoyang.ren
 * @date:Jun 22, 2017
 * @time:4:16:24 PM
 * @email:chaoyang.ren@foxmail.com
 * @version: 1.0
 */
package pattern.behavioral.Interpreter.simple;